Aerosol composition compatible with excess propellant

ABSTRACT

AN AEROSOL COMPOSITION CONTAINING AS ESSENTIAL INGREDIENTS A PROPELLENT, AN AQUEOUS SOAP SOLUTION AND A FATTY ACID ESTER AMIDE OF THE FOLLOWING STRUCTURAL FORMULA:   RCONHCH2CH2OOCR1   WHEREIN R AND R1 INDEPENDENTLY REPRESENT ALKYL CONTAINING FROM 12 TO 20 CARBON ATOMS.

United States Patent Ofiice In. or. one 17/04 US. Cl. 252-90 6 Claims ABSTRACT OF THE DISCLOSURE An aerosol composition containing as essential ingredients a propellant, an aqueous soap solution and a fatty acid ester amide of the following structural formula:

RCONHCH CH OOCR wherein R and R independently represent alkyl containing from 12 to carbon atoms.

This application is a continuation-in-part of copending US. application Ser. No. 726,197, filed May 2, 1968 now abandoned, which is a continuation-in-part of U.S. application Ser. No. 468,588, filed lune 30, 1965, now abandoned.

The present invention relates in general to compositions beneficially and advantageously adapted for use in connection with aerosol applications and in particular to the provision of improved lather-producing compositions for such purposes.

As is well known, aerosol methods of dispensing latherproducing compositions have met with a considerable measure of commercial success, e.g., compositions specifically adapted for the production of lather for shaving, shampooing or other and related Washing, cleansing, etc., operations. In general, aerosol, lather-producing compositions make possible a much more highly efficient means for product application to, for example, human skin. Thus, it is invariably found that significant increase in areacoverage efiiciency is attainable with aerosol methods of dispensing.

Despite the aforementioned advantages, considerable difficulty has nevertheless been encountered as regards the provision of compositions capable of yielding high foam volume, desired lather quality, etc., according to procedures which tend to minimize cost, handling requirements and the like.

In order to remedy the foregoing situation, considerable industrial activity has centered around the research and development of lather-producing compositions capable of substantially complete expulsion from a pressurized aerosol container whereby to yield a foam or lather product of optimum texture, feel, etc. Invariably, however, the remedial techniques thus far promulgated have provided only marginal improvement; thus, attempts to incorporate excess quantities of propellant have been vitiated due to the concomitant, deleterious effects upon foam or lather quality, difiiculties of dispensing, etc., thereby virtually eliminating any possibility of providing a product of quality sufficient to comply with commercial requirements. Thus, for example, it has been ascertained in practice that significantly increasing the over-all weight ratio of propellant to lather-producing compositions inevitably results in an aerosol lather product having highly objectionable properties such as being of rubbery, stiff texture or otherwise aesthetically displeasing for contact with the human skin, hair, etc. Further difficulties surrounding attempts to formulate high quantity propellant-containing compositions concerns problems associated with sputtering; thus,

3,758,411 Patented Sept. M, 1973 efiicient aerosol dispensing of compositions so formulated proves impossible as a practical matter since the tendency of the composition to sputter results in considerable loss of product due to the fact that complete exhaustion of propellant precedes total expulsion of product.

Apparently the genesis of the problems involved derives from the failure of the lather-producing ingredients and aerosol propellant to form an emulsion of the requisite stability, quality, etc. Accordingly, it becomes necessary in practice to resort to the use of auxiliary means by which to promote the desired product stability. Thus, it is conventional practice in the manufacture of aerosol products to subject the aerosol container, prior to shipment to a heating operation in order to effect curing of the container ingredients. This is accomplished, for example, by heating the packaged aerosol composition to temperatures approximating F. for relatively protracted periods of time, e.g., on the order of at least 20 minutes. Moreover, it is absolutely imperative that the aerosol containers be subjected to vigorous agitation, e.g., shaking, during shipping in order to insure the requisite product stability. Apparently, maintaining the aerosol containers under constant agitation serves to arrest or otherwise retard any tendency of the product composition to deemulsify.

As will be recognized, operations of the aforedescribed nature can be intolerably cumbersome in view of the rather stringent requirements imposed upon those responsible for the handling of the packaged aerosol product. Moreover, it is invariably found that the aerosol product as supplied to the consumer is nevertheless characterized by inferior properties despite the observance of such precautionary measures, whether the amount of propellant present in the aerosol formulation be conventional or otherwise.

In accordance with the discovery forming the basis of the present invention, it has been ascertained that latherproducing compositions specifically adapted for aerosol applications can be synergistically modified to advantage by the inclusion therein of a further additive selected from a relatively delimited class of compounds.

Thus, a primary object of the present invention resides in the provision of aerosol, lather-producing compositions wherein the foregoing and related disadvantages are eliminated or at least mitigated to a substantial extent.

Another object of the present invention resides in the provision of aerosol, lather-producing compositions capable of providing a foam or lather product upon aerosol dispensing having optimum properties as regards texture, feel, and the like.

A further object of the present invention resides in the provision of aerosol, lather-producing compositions compatible with propellant quantities substantially in excess of those conventionally employed.

A still further object of the present invention resides in the provision of aerosol, lather-producing compositions wherein any necessity for extended heat-curing operations, the maintaining of agitation conditions during transit, etc., is completely obviated.

Yet another object of the present invention resides in the provision of aerosol, lather-producing compositions possessed of a high degree of exhaustion efficiency leading to manifold increase in volume of product foam.

Other objects and advantages of the present invention will become more apparent hereinafter as the description proceeds.

The attainment of the foregoing and related objects is made possible in accordance with the present invention which in its broader aspects includes the provision of aerosol compositions comprising: (I) a propellant selected from the group consisting of saturated aliphatic hydrocarbons containing from 2-4 carbon atoms, halogenated hydrocarbons containing from l-2 carbon atoms and mixtures thereof, and (II) a lather-producing component containing as essential ingredients: (a) a water soluble soap selected from the group consisting of C C saturated and unsaturated fatty acids, sodium C -C alkyl benzene sulfonate, sodium lauryl sulfate and mixtures thereof, present in an amount of about 3-30% by weight (b) water present in an amount of at least 70% by weight, and (c) a fatty acid ester amide of the following structural formula:

wherein R and R independently represent alkyl containing from 12 to 20 carbon atoms and present in an amount of about 01-10% by weight of the lather-producing composition, the weight ratio of (II) to (I) being within the range of from about 5:1 to about 70:1 said composition exhibiting higher foam volume and compatibility with larger amounts of propellant than similar compositions not containing said ester-amide.

The fatty acid ester amides contemplated for use in accordance with the present invention are uniquely typified in that their use in compositions of the type herein described permit the incorporation of propellant materials in unusually high quantities in the total absence of the deleterious effects characterizing compositions heretofore promulgated in the art such as sputtering, inferior product texture, feel, etc. The importance of this particular advantage cannot be overemphasized since it bears directly upon the amount of aerosol product which is retrievable from a given container. In general, the concentration of propellant in the compositions herein described can be of such magnitude as to permit the 0btention of foam volume which approximately double those heretofore obtainable utilizing the identical amounts of lather-forming ingredients. This aspect can be illustrated by reference to the fact that aerosol products commercially available in nominal six ounce containers generally provide from about 1400 to about 1700 cubic centimeters of lather with the use of a feasible maximum of 5.1 grams of hydrocarbon propellant to about 180 grams of lather-producing composition, the latter being comprised primarily of an aqueous soap solution. In contradistinction, aerosol products formulated in accordance with the present invention are capable of yielding approximately 3400 centimeters of superior quality lather or foam by increasing the quantity of propellant employed, the lather being made feasible by the presence of the fatty acid ester amide.

The compositions of the present invention likewise offer significant advantage when prepared using conventional propellant quantities. Thus, it is found in such circumstances that the lather product obtainable possesses superior properties as regards texture, feel, etc. Moreover, the presence of the fatty acid ester amide eliminates entirely any need for agitation-in-transit or extensive heat curing prior to shipment. Without intending to be bound by any theory, it is postulated in explanation of the foregoing that the presence of the fatty acid ester amide serves to augment or otherwise promote compatibility of the involved ingredients, e.g., propellant, soap solution, as well as any other auxiliary ingredients which might be present. The increased compatibility is manifested in the form of a more stable aerosol product, i.e., the tendency of the ingredients to de-emulsify or otherwise separate is minimized if not eliminated. In this manner there is obtained a more uniform product throughout the aerosol container.

Heretofore, attempts to employed increased amounts of propellant have proved particularly problematical in connection with propellant materials of the aliphatic hydrocarbon type, i.e., as to be distinguished from the halogenated hydrocarbon propellants as typified by those c m e y ai able under th t ade ame d ignations Freons and Genetrons. Accordingly, it is conventional, if not necessary, practice in the art when preparing aerosol, lather-producing compositions employing aliphatic hydrocarbon-propellants to confine the soap solution/hydrocarbon propellant weight ratio within the range of 40 to 50:1 and higher. Attempts to increase the quantity of propellant in such instances prove largely ineffective and self-defeating since the resulting aerosol product is characterized rubbery or stiff thereby producing a sputtery foam. Thus, the present invention proves particularly beneficial in connection with aerosol compositions formulated with propellants of the aliphatic hydrocarbon type.

The fatty acid ester amides contemplated for use in accordance with the present invention may be employed either singly or in admixture. Suitable for use are monoethanol amide esters of straight and branched chain, saturated and unsaturated C C more preferred C to C fatty acids or mixtures thereof. For example, one such compound found to be particularly effective is a monoethanol amide ester of a mixture of saturated straight chain G to C fatty acids.

In any event, the fatty acid ester amide compound may be readily and conveniently prepared by reacting, for example, ethanol amide (H NCH CH OH) with the fatty acid material whereby to form the corresponding fatty acid ester amide derivative. As will be recognized, this manner of preparation involves the acylation of both the amino and hydroxyl groups, i.e., simultaneous amidification and esterification. This method of synthesis is preferable in those instances wherein it is desired that the R and R moieties in the above depicted structural formula be identical. Alternatively, the amidification and esterification reactions may be carried out separately, i.e., sequentially; this particular procedure is preferable in the preparation of fatty acid ester amides having different acyl moieties. In any event, the particular fatty acid selected must be one having the requisite number of carbon atoms in accordnace with the structural formula hereinbefore given.

The amount of fatty acid ester amide employed may be rather minimal in comparison to the other ingredients comprising the essential components of the subject compositions. In any event, optimum realization of the improvements described herein can be obtained with the use of the fatty acid acide in concentrations ranging from about 0.1% to about 10% by weight of the soap solution, the latter comprising the soap and water components, with a range of about 0.5% to about 5.0% being particularly preferred. Selection of a specific concentration within the aforestated range will be influenced to a great extent by, for example, the type of propellant material employed. Thus, in the case of hydrocarbon propellants, increased quantities of atty acid ester amide are usually preferable while in the case of halogenated hydrocarbon propellants, it is usually found that lesser amounts suflice. It will further be understood that departures from the aforestated ranges may be dictated in a particular circumstance depending upon the requirements of the formulator.

The nature of the soap or detergent material employed in the compositions described herein is not particularly critical and thus may be selected from any of those water soluble soap materials conventionally employed in the preparation of lather-producing compositions of the type utilized in shaving creams, shampoos, etc., such as the water soluble soaps of higher fatty acids. Suitable for use are water soluble soaps selected from the group consisting of sodium, potassium, ammonium, triethanol amine, morpholine C C fatty acids and mixtures thereof. More suitable soaps include the soluble stearate soaps such as the sodium, potassium, ammonium and soluble amine soaps of commercial stearic acid with particularly preferred representatives including the sodium-potassium soaps of commercial, double-pressed stearic acid, e.g.,

triethanol amine stearate, morpholine stearate, triethanol amine myristate, and the like. The stearates may be produced by neutralization of stearic acid with alkali or alternatively may be introduced in the form of animal fats such as tallow, the latter containing high quantities of stearic acid. Mixtures of stearate soaps may also be used if desired in Order to assure the obtention of a soap material having the desired consistency. The latter is particularly significant in connection with the preparation of shaving lather compositions. Vegetable oil soaps may likewise be employed and in fact are particularly recommended for use in the preparation of shampoo compositions. In addition, vegetable oil soaps may be employed to advantage in admixture with soluble soaps of the stearic acid type in the preparation of shaving lather compositions, the presence of the vegetable oil soap serving to minimize any tendency of the resulting soap solution to gel or otherwise undergo undesired increases in viscosity at low temperatures.

The amount of soap employed in the preparation of compositions described herein may vary within relatively wide limits, this aspect comprising a relatively non-critical factor in the practice of the present invention, apart from the obvious requirement that the soap material be employed in amounts sufiicient to yield a Satisfactory lather. In general, the minimum amount of soap employed will be governed by the latter mentioned factor. The maximum amount of soap employed is governed primarily be economic considerations. However, the use of excess quantities of soap may very likely give rise to problems associated with gel formation at lower temperature ranges. Accordingly, the maximum amount of soap employed should be such as to substantially resist any tendency to form a gel at the temperature ranges likely to be encountered in use. In any event, it is usually found that the employment of soap in amounts approximating from about 3 to about 30 percent by weight of the soap in water solution sufiice for the vast majority of applications contemplated with a range of from about 5 to about 20% being particularly preferred. As particular examples of soap materials found to be eminently suitable for use in the present invention there may be mentioned without necessary limitation the following:

sodium and potassium soaps of commercial double pressed (stearic acid) triethanol amine stearate triethanol amine soap of coconut oil fatty acids morpholine stearate sodium lauryl sulfate triethanol amine lauryl sulfate sodium alkyl benzene sulfonate polyoxyethylene ethers of alkyl phenols etc.

The amount of water employed will, of course, be determined by the concentration of soap desired in the lather-producing composition. For most applications, the water will usually comprise at least about 70% by weight of the composition.

The propellant materials suitable for use in the practice of the present invention comprise in general any of those conventionally employed in the formulation of aerosol products, i.e., non-toxic, liquefied, normally gaseous, saturated, low molecular weight hydrocarbon and halogenated hydrocarbons. Suitable aliphatic hydrocarbon propellants include, for example, ethane, propane, butane, isobutane, etc. In general, aliphatic hydrocarbon propellants containing from 2 to 4 carbon atoms are preferred for use. As examples of suitable halogenated hydrocarbon propellants there may be mentioned in particular and without necessary limitation, dichlorodifluoromethane, 1,2-dichloro-1,1,2,2-tetraiiuoromethane; monofluorotrichloromethane; trichlorotrifiuoroethane, etc.

The propellant material whether of the hydrocarbon or halogenated hydrocarbon type is employed in concentrations sufiicient to yield a lather-producing composition/ propellant weight ratio in the range of from about 5:1 to :1. As explained hereinbefore, the presence of the fatty acid ester amide material makes possible the provision of superior lather or foam producing compositions whether the propellant material be employed in excess or conventional quantities. Thus, within the broad range specified, the selection of a particular concentration of propellant capable of providing optimum advantage for the application at hand can be readily determined by one having reasonable skill in the art.

The propellant, fatty acid ester amide and aqueous soap solution comprises the essential ingredients of the composition described herein. However, it will be understood that varying proportions of further additives of an optional nature may likewise be included for purposes of achieving one or more desired effects. Ingredients of this type are, of course, well known in the art and include, for example, skin fresheners, lather stabilizers and the like such as glycerine, lanolin, lecithin, coconut oil, fatty acids, fatty amides, etc.; perfume, etc.

If desired, additional ingredients may be included for purposes of promoting solubilization of the various components of the lather producing formulation. Thus, lower molecular Weight aliphatic alcohols and preferably lower monohydric alcohols, e.g., methanol, ethanol, normal propanol, isopropanol, etc., may be employed for such purposes.

Auxiliary ingredients of the aforedescribed type may be added in any desired amount with the obvious limitation that their proportions be confined within limitations Whch assures the absence of deleterious effects. In any event, it is conventional practice to include such materials in amounts sufficient to yield a concentration within the range of from about 0.1 to about 10% by weight of the total composition.

The lather-producing compositions described herein may be prepared in any suitable manner. Thus, for example, one satisfactory method comprising dissolving the soap or detergent material in water and thereafter adding the fatty acid ester amide compound. The latter composition is thereafter introduced into the aerosol container. The propellant, under pressure, may then be admitted to the container through a valve or other appropriate means, the container preferably being slightly chilled during the addition.

The following examples are given for purposes of illustration only and are not to be considered as necessarily constituting a limitation on the present invention. All parts given are by weight unless otherwise indicated.

EXAMPLE 1 An aerosol shave cream composition is prepared utilizing the following ingredients in the proportion stated:

The diethanol amide of a 70 :30 (by Weight) mixture or lauric and myristic acids.

Coconut oil fatty acid is a mixture of Ca to C13 fatty acids comprising approximately 48% lauric acid, a myristic acid, 9% palmitic, 2.1% stearic, 5.7 oleic, 2.6% linoleic, 7.9% caprylic, and 7.2% capric.

The stearic monoethanol amide ester employed in this example is a mixture of monoethanol amide esters of straight chain, saturated CLO-C15 fatty acids of which stearic acid is one. It is marketed by Van Dyk and Company under the trade name Cerasynt D and has an acid number of 10-20, free stearic acid of 36-72%, saponification number 98-108 and an iodine value of 0.5 maximum.

Approximately 177 grams of the above formulation are charged to an hermetically sealed 6 ounce container and thereafter pressurized with 10.2 grams of a propellant blend consisting of 87% isobutane and 13% propane, whereby to yield a soap-water-fatty acid ester amide propellant weight ratio of about 16.5. The aerosol container is then cured at 130 F. for only five minutes. At no time is the aerosol container subjected to shaking or agitation of any kind. Dispensing of the aforedescribed formulation from the aerosol container yields approximately 3400 cubic centimeters of lather product. The lather thus obtained was of excellent texture, feel, etc., and of highly uniform composition throughout indicating that homogeneous and intimate dispersion of the involved ingredients obtained. In addition, it was noted that nothing in the way of sputtering or similar effects accompanied expulsion of the aerosol composition.

The aforedescribed procedure is repeated except that the fatty acid ester amide material is omitted from the shave cream formulation. In this instance, the aerosol container is cured at 130 F. for a period of 20 minutes and thereafter subjected to vigorous shaking. Expulsion of the aerosol contents resulted in the formation of a rubbery, sputtery product which proved to be highly unsuitable 8 evaluated in terms of texture, feel, uniformity of composition as well as total volume of foam available for a given quantity of composition.

Evaluation of the individual lather-producing compositions tested establishes unequivocally the superiority of the fatty acid ester amide-containing compositions encompassed by the present invention when compared to control compositions otherwise identical except for the omission of the fatty acid ester amide compound. In each case, the quantity of lather obtainable with the compositions of the present invention at least double in volume the quantity of foam obtainable with corresponding control compositions. Of equal importance, the lather products obtained with the compositions of Examples 215 were of excellent texture and feel, being smooth, aesthetically pleasing and non-rubbery to the touch. Of primary importance is the result that in each case, the aforedescribed advantages were obtaintable despite the fact that the pack aged aerosol compositions were subjected to nothing in the way of agitation, shaking, etc. Moreover, heat-treatment periods comprising but a fraction, i.e., on the order of one-fourth of those necessary with conventional aerosol lather-producing compositions were suificient for purposes of accomplishing the requisite degree of curing.

Fatty acid ester amide FAEA) Weight RCONHCHBCHZ ratio OCR1 p Propellant FAEA- soap-water] R Parts Compound Parts CompounrP Parts propellant O 5.0 Triethanol amine stearato 10 1 16.6 1 01 1.5 12 4 10.0 9:1 Om 4.0 do 9 2 4.8 20:1 015 3. 0 Morpholine stearate 6 5 2. 4 10:1 O 1.2 do 14 6 6.25 :1 C1 0.5 do 18 7 11.1 8:1 015 0. 6 Triethanol amine soap of 2 2. 4 :1

coconut oil fatty acids. Om 2.0 do 10 8 10.6 5:1 C20 0.5 do 15 1 1.4 70:1 C20 0. 8 Na lauryl sulfa 15 3 10. 6 5:1 C1 1.0 do 13 8 2.4 40:1 Cit 0. 5 Na and K stearate. 8 4 1. 4 70:1 Cm 0.3 do 5 3 10.0 9:1 11 0- d0 0 7 1.96 :1

*Compound 1. butane; 2. propane; 3. isobutaue (87%), propane (13%); 4. dichlorodifluoromethane; 5. trichlorotrifluoromethane; 6. isobutaue; 7. monofluorotrichloromethane; 8. 1,Z-dichloro-l,1,2,2-tetrafluoroethane.

for shaving application. In addition, only 1700 cubic centimeters of product were retrieved from the aerosol container. In fact, it was found that shaving cream formulations prepared but omitting the fatty acid ester amide were capable of tolerating only about 5.1 grams of propellant (per 177 grams of total formulation) whereby to yield an even remotely satisfactory lather product upon dispensing from an aerosol container. Attempts to increase the amount of propellant beyond such value were vitiated by the prounounced tendency of the composition to form upon aerosol dispensing a sputtery, rubbery-textured lather of non-uniform composition. In addition, product yield was intolerably low.

EXAMPLES 2-15 A series of lather-producing compositions for shaving cream applications is prepared utilizing a simple mixture of fatty acid ester amide, aqueous soap solution and propellant in varying quantities as indicated in the following table. In each case, the composition in question contains the fatty acid ester amide, soap and propellant in the proportions stated with the balance of the composition comprising water, i.e., sufiicient to make 100 parts of total formula.

Each of the compositions thus prepared is charged to a six ounce hermetically sealed container and thereafter pressurized with propellant in the manner described in Example 1. In order to determine the properties of each of the compositions tested, the lather product obtained is The results obtained tend to indicate that the halogenated hydrocarbon propellant materials may be more readily incorporated in greater amounts than is possible with propellants of the hydrocarbon type. In such cases, however, the presence of the fatty acid ester amide proves highly beneficial since it obviates completely any requirement for mechanical agitation of the aerosol container for purposes of expediting the attainment of a satisfactory aerosol foam. In contradistinction, the use of halogenated hydrocarbon propellants in increased quantities in compositions devoid of the fatty acid ester amide fails to obviate the agition requirement as a condition to the obtention of a satisfactory product. Of further significance is the fact that the noted improvements as regards quality of lather, volume of foam obtainable with a predetermined quantity of lather-producing composition, etc., are readily obtainable despite the employment of the fatty acid ester amide in relatively minor proportions.

The present invention as is evident from the above description relates in one of its aspects to an improved lather-producing composition comprising propellant, water soluble soap, and water, wherein the improvement comprises that also present is a fatty acid ester amide of the following structural formula:

RCONHCH CH OOCR wherein R and R independently represent alkyl containing from 12 to 20 carbon atoms. The fatty acid ester amide provides a lather composition of superior quality compatible with propellant in excess of amounts permitted in the absence of said fatty acid ester amide. As a result, the lather compositions containing additional propellant supply larger volumes of superior lather.

The present invention has been described with respect to certain preferred embodiments thereof and there will become obvious to persons skilled in the art other variations, modifications and equivalents which are to be understood as coming within the scope of the present invention.

What is claimed is:

1. An aerosol composition consisting essentially of:

(I) a propellant selected from the group consisting of saturated aliphatic hydrocarbons containing from 2-4 caruon atoms, halogenated hydrocarbons containing from 12 carbon atoms and mixtures thereof; and

(II) a lather-producing component containing as essential ingredients: (a) a water soluble soap selected from the group consisting of C -C saturated and unsaturated fatty acids, sodium C -C alkyl benzene sulfonates sodium lauryl sulfate, and mixtures thereof, present in an amount of about 15-30% by Weight (b) Water present in an amount of at least 70% by weight, and (c) a fatty acid ester amide of the following structural formula:

RCONHCH CH OOCR wherein R and R independently represent alkyl containing from 12 to 20 carbon atoms and present in an amount of about 0.1-10% by weight of the latherproducing composition, the weight ratio of (II) to (I) being within the range of from about 5:1 to about 70:1 said composition exhibiting higher foam volume and compatibility with larger amounts of propellant than similar compositions not containing said ester-amide.

2. An aerosol composition according to claim 1 wherein said fatty acid ester amide is a monoethanol amide ester of C -C fatty acids.

3. An aerosol composition according to claim 1 wherein said water soluble soap is selected from the group consisting of sodium, potassium, ammonium, trielhanol amine, and morpholine C C fatty acids.

4. An aerosol composition according to claim 1 wherein said water soluble soap is a sodium-potassium soap of stearic acid.

5. An aerosol composition according to claim 1 Wherein said fatty acid ester amide is present in an amount of about 0.5% to about 5.0% by weight.

6. An aerosol composition according to claim 1 wherein said Water soluble soap is sodium stearate present in amounts ranging from 5 to about 20% by weight.

References Cited UNITED STATES PATENTS 2,879,231 3/1959 Allen et al. 252 2,908,650 10/1959 Fine 25290 2,968,628 1/1961 Reed 252-305 3,040,075 6/1962 Lohr 260-404 3,024,260 3/1962 Ernst 260-404 3,262,951 7/1966 Katz 260-404 3,373,173 3/1968 Foley et a1 260-404 OTHER REFERENCES Sagarin: Cosmetics, Science & Techn., 1957, pp. 803, 804, 811, 815.

WILLIAM E. SCHULZ, Primary Examiner US. Cl. X.R.

252305, DIG.13; 424--73 

